Appendix A. Descriptions
of the spatial, land cover, and environmental variables obtained from the NLCD
and MBSS data sets, including distance-matrix assignments corresponding to matrices
used in the partial Mantel analysis, transformation applied prior to variable
inclusion into distance matrices, and summary statistics of each untransformed
variable (N = 295 stream sites sampled).

Variable
(units)

Distance
matrix

Transformation

Minimum

Maximum

Median

Mean

SD

Latitude (decimal-degrees)

Space

none

38.06

39.62

38.85

38.82

0.33

Longitude (decimal-degrees)

Space

none

76.31

78.22

77.55

77.33

0.53

Watershed area
(ha)

Watershed Area

log10

8.2

29
929

2814

2932

4106

Developed (% watershed
area)

% Developed

none

0.0

87.7

4.6

12.8

19.1

Forested (% watershed
area)

NA†

NA

1.8

100

43.9

46.9

19.7

Cropland (% watershed
area)

% Cropland

none

0.0

87.5

10.5

18.6

17.7

Wetland (% watershed
area)

% Wetland

none

0.0

35.2

4.6

7.2

7.5

Riparian shading
(% canopy closure)

Riparian

arcsin(sqrt)

5.0

99.0

75.0

68.9

23.8

Riparian remoteness
(integer rating, 020)

Riparian

none

0

20

10

10.3

5.5

Riparian aesthetic
rating (integer rating, 020)

Riparian

none

0

20

15

12.6

5.1

Riparian buffer
(minimum width, m)‡

Riparian

log10

0.0

50.0

40.0

31.0

5.5

Slope (%)

Gradient

log10

0.0

3.00

0.31

0.52

0.47

Mean velocity (m/s)

Gradient

log10

0.0

0.51

0.10

0.11

0.10

Velocity-depth
diversity (integer rating, 020)

Gradient

none

0

18

10

9.5

4.2

Maximum depth (cm)

Size

log10

1.5

200

61.0

64.6

33.8

Mean width (m)

Size

log10

0.05

23.5

3.7

4.7

3.8

Mean thalweg depth
(cm)

Size

log10

1.5

84.3

28.0

31.2

18.4

Temperature (°C,
field)

Temp

log10

11.4

30.9

20.4

20.5

3.4

Dissolved oxygen
(mg O2/L, field)

DO

log10

0.30

14.0

7.51

7.12

2.20

pH (lab)

Acidity

none

4.00

8.87

6.71

6.69

0.60

Acid neutralizing
capacity (µeq/L, lab)

Acidity

log10

0.0

2456

300

419

390

Specific conductivity
(µS/cm, lab)

Cond

log10

38

2418

152

183

184

Dissolved organic
carbon (mg/L, lab)

DOC

none

0.9

32.9

4.8

5.9

4.3

Nitrate-nitrogen
(mg/L, lab)

NO3-N

log10

0.0

16.2

1.10

2.03

2.41

In-stream habitat
(integer rating, 020)

SubQual

none

0

19

11

10.9

4.5

Epifaunal substrate
(integer rating,020)

SubQual

none

0

18

10

9.1

4.6

Pool quality (integer
rating,020)

SubQual

none

1

20

13

11.6

4.4

Riffle quality
(integer rating,020)

SubQual

none

0

19

10

9.5

5.2

Embeddedness (%)

SubQual

arcsin(sqrt)

0

100

80.0

70.1

31.3

Woody debris and
root wads (total no.)

Woody

log10

0

37

7

7.9

6.6

†NA = not
applicable. Percentage forested was not included in the partial Mantel analysis